The present invention relates to rowing machines, and relates more particularly to such a rowing machine in which the seat frame oscillates up and down when the sliding seat is reciprocated on the seat frame during the operation of the machine.
FIG. 1 shows a conventional rowing machine. This structure of a rowing machine comprises a flat and elongated seat frame, two handles supported on a respective hydraulic cylinder for rowing, and a sliding seat slidably mounted on the seat frame for sitting. The two opposite ends are fixedly secured in place. When the rowing machine is operated, the sliding seat is reciprocated on the seat frame.
The present invention provides a rowing machine which permits the seat frame to oscillate up and down when the sliding seat is reciprocated on the seat frame.
According to the preferred embodiment of the present invention, the rowing machine comprises a base frame, a flat and elongated seat frame, a sliding seat sliding on the seat frame, two handles pivoted to the base frame and arranged with a respective hydraulic cylinder, providing resistance to rowing action, and two pedals respectively supported on the base frame by arm pedals bars. The seat frame has a front end pivoted to one end of the base frame and a rear end connected to an opposite end of the base frame by a hydraulic cylinder. A rocker arm (or lever) is pivoted to the base frame. The rocker arm is arranged to permit the seat frame to oscillate up and down when the sliding seat is moved back and forth on the seat frame during the operation of the machine. The rocker arm comprises a front end arranged underneath the seat frame near its front end, a rear end coupled with a roller disposed in contact with the seat frame, a middle part disposed at a lower elevation than the front end and rear end of the rocker arm and pivoted to a middle support on the base frame by a pivot, and two pedal bars connected to the front end thereof at two opposite sides to hold the pedals.